To find the percent yield of CO2, we need to compare the actual amount produced in the lab (20.0 g) to the theoretical maximum amount that could have been produced based on the amount of CaCO3 that reacted (50.0 g).
First, we need to determine the theoretical maximum amount of CO2 that could have been produced. To do this, we need to find the stoichiometric amount of CO2 produced from the reaction:
CaCO3(s) -> CaO(s) + CO2(g)
1 mole of CaCO3 reacts with 1 mole of CO2 produced. The molar mass of CaCO3 is 100.09 g/mol, so we can convert 50.0 g of CaCO3 to moles:
50.0 g CaCO3 / 100.09 g/mol = 0.498 mol
The theoretical maximum amount of CO2 produced is then:
0.498 mol CO2 * 44.01 g/mol = 21.97 g
Finally, to find the percent yield, divide the actual amount of CO2 produced in the lab (20.0 g) by the theoretical maximum amount (21.97 g) and multiply by 100:
Percent yield = (Actual yield / Theoretical yield) * 100
Percent yield = (20.0 g / 21.97 g) * 100 = 91.3%
So, the percent yield of CO2 is 91.3%.